Manu Tuilagi scored two tries as England launched their bid for a second Rugby World Cup title with a comfortable but error-strewn 35-3 bonus-point win over Tonga on Sunday.
The Samoa-born centre crossed twice under the Sapporo Dome roof in a first half that ended with England well ahead at 18-3.
And second-half scores from hooker Jamie George and replacement Luke Cowan-Dickie saw England secure a bonus point for scoring four tries, a result that could be crucial in a tight Pool C.
In addition England, playing within themselves, also appeared to avoid any injuries to key players.
"We had to toil hard today and I was particularly pleased at the end of the game when we were under the pump a bit, we defended really well," said Jones.
"That's two Tests now we haven't conceded a try so we're pretty happy with that. We'll just build our game as we go along.
"We'd like to be sharper with the ball and that will come. But I was really pleased with the efforts of my players. They worked hard and what a great effort by Tonga. They fought really hard."
England, whose humiliating first-round exit on home soil at the 2015 World Cup led to Jones's appointment as coach, took an 11th-minute lead when captain Owen Farrell scored the first of his 15 points with a penalty.
Tonga scrum-half Sonatane Takulua equalised three minutes later after a thumping hit by flanker Zane Kapeli on England number eight Billy Vunipola, whose father and uncle both played in the Tonga side thrashed 101-10 by England at the 1999 World Cup.
England thought they had scored the opening try when flanker Sam Underhill charged over after fullback Elliot Daly ran a loose kick back.
But with the grounding unclear to the television match official, the score was disallowed.
From the resulting five-metre scrum, however, Tuilagi bundled over for a 24th-minute try which the TMO did award. Farrell missed the conversion but England still led 8-3.
England lock Maro Itoje then gave away a penalty to the obvious fury of Jones, in charge of his native Australia when England beat the Wallabies in the 2003 World Cup final in Sydney.
But Takalua was off target and his miss was made worse for Tonga, hammered 92-7 by world champions New Zealand in a warm-up match this month, when Tuilagi scored his second try.
Daly released Jonny May and the left wing made a surging run before his well-timed inside pass to Tuilagi allowed the midfielder to charge in in the 31st minute.
Farrell converted and England led 15-3.
England, declining a kickable penalty, almost had another try before half-time.
But, with Tonga defending desperately on their own line, an infringement led to a penalty in front of the posts which Farrell landed to give England a comfortable 15-point advantage at half-time.
Farrell made it 21-3 early in the second half with a 39-metre penalty and now it seemed as if the only issue remaining was whether a Tonga team coached by Toutai Kefu, who played under Jones for Australia, could stop England scoring four tries.
England, after Sam Underhill knocked-on when well-placed, eventually scored their third try when a thunderous rolling maul saw hooker Jamie George power over in the 57th minute.
But England lost momentum as Jones rang the changes, although their fourth try did arrive three minutes from time when wing Anthony Watson's surging run and pass released Cowan-Dickie.
England now have a quick turnaround before their next Pool C match against the United States in Kobe on Thursday, with Tonga playing Argentina, looking to bounce back from an agonising loss to France, on Saturday.